Cam-operated switch.



G: A. BURNHAM.

CAM OPERATED SWITCH. APPUCATION FILED JUNE 23. ml.

1 1 8 1 ,73 3 Patented May 2, 1916.

2 SHEETS-SHEET I.

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CAM OPERATED SWITCH.

APPLICATION FILED 1umz23, 1911.

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GEORGE A. BURNHAM, OF CLIFTONDALE, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

CAM-OPERATED SWITCH.

Application filed June 23, 1911.

To all whom it may concern:

Be it known that I, GEORGE A. BURNHAM, a citizen of the United States, residing at Cliftondale, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Cam- Operated Switches, of which the following is a full, clear, and exact specification.

This invention relates to the operating means for electric switches, which switches are adapted for automatic control when. desired.

The particular object is to provide a double throw mechanism by the provision of controlling means which is simple in construction and wherein a single device is adapted for successively closing the ditto! out parts of the switch.

Another object is to provide operating means of this character which will occupy a minimum space on the switch-board or other support.

The switch is especially adapted for starting electric motors, a movement of the con trolling means in one direction throwing the motor in circuit through a compensator, and in theother direction, throwing it directly on the line. In the present instance, a plurality of vertically reciprocating movable contacts are provided to engage terminals connecting witln the line.

Various other objects and features of my invention will be understood from the following description and accompanying drawmgs.

Figure l is a part sectional view of an oil switch embodying my invention; Fig. 2 is an elevation at right angles to the plane of Fig. I; Fig. 3 is a detailed view of the trip bar partly raised and as seen when looking in the direction of the arrow on Fig. 4; Fig. 4 is a top plan view of the switch, and Fig. 5 is a diagram of the circuit connections.

A horizontal supporting plate or bracket 1 is adapted to be mounted on a switch-board panel or other support and supports all parts of the switch and operating mechanism.

2 is a galvanized iron oil can removably connected to the support 1 by wing nuts 3, 3, etc. An insulating board dis secured to the underside of the plate 1 and in which are secured six fiber tubes 5, 5?, etc., through which are led the terminals which connect Specification of Letters Patent.

Patented May 2, 1916.

Serial No. 635,048.

with the line wires. The fixed switch termmals are six L shaped copper bars 6, 6 and three plates 7 are supported in the same plane as the bent ends of the bars, to which plates are connected the three lines from the motor. Elastic bridging contacts 8, 8, six in number, are secured to two wooden blocks 9, 9 the block 9 carrying the three bridging contacts 8 and the block 9 carrying the three bridging'contacts 8. These blocks are secured respectively to two metal yokes 10, 10 so as to slide up and down in companion yokes 11, ll secured to the wooden board 4.

Toggles 12, 12 each have one link pivoted respectively on cross pins 13 fixed on the yokes 1 1, ll, and the toggles each have the other link pivoted respectively on cross pins 13 adapted to slide up and down in slots 14 in the fixed yokes l1, 11, the pins 13 being connected respectively, to yokes 10, 10. Helical compression springs 15, 15 urge the bridging contacts to open position. The pins 16 forming the knuckle of each to gle cooperate respectively with operating liars 17, each of the latter being provided with a sloping wall 19 in the end of a cir-- in the line of or slightly over the center, as

indicated in the dotted position in Fig. 2. In this position the end of the operating bar 17 extends over a trip piece 22 secured to a pivoted bar 23, the rear end of which lies in the upward path of the plunger of the trip magnet 24.

The forward end of each trip bar 17, 17 is pivoted respectively in a rocking yoke 25 on a lateral extension of which is pivoted a roller 27. The bar 17 is shorter than the bar 17 as shown in Fig. 4 and is not adapted for automatic tripping. Either bar may be separately moved forward by a cam 28 formed as an oblique section of a cylinder pivoted on a stud 29, the axis of which is half-way between the two yokes ll, 11. When the cam is turned upon the stud 29 to the right in Fig. 1, the inclined face of the right hand half of thecam engages one of the rollers 27 and forces it, together with bar 17, toward the rear of the-switch. The notch so of bar 17 being in engagement with pin 16, ti -:roiiperating toggle is straightened or carried slightly beyond its dead center position. This action closes the cor" responding switch contacts 8 and the gle holds the same in closed position. In the same way, when the cam is turned to the left from the position shown in Fig. 1, the same action of the other parts takes place u. motacts 8, the other half of the inciin' .race of the cam 28 in this case en gaging roller 27 of thehar 17.

An operating handle 30 is fixed to the cam 28. The operating handle is l'iollow and contains a spring pressed finger piece 31 and a hook 32 which latter engages with a latch pivoted at 33* to the cam In the mid-position of the handle as shown in the drawings, the inner end of the latch clined face of the left-hand portion of the cam then engaging the roller 27 of the liar 17 and results in straightening the toggle 12 and closing the bridging contacts 8, giv ing circuit connections corresponding to closing the circuit between the middle and upper contacts of Fi g. 5, thus cutting in the three phase motor 34: on partial voltage through the compensator 35. A moveinent V of the handle and cam is then made in the reverse direction and the bridging contacts are thereby shifted into engagement as above described, giving circuit-connections corresponding to closing the circuit between the middle and the lower set of contacts of Fig. 5, which connects the motor directly to the supply line.

In the particular application herein illustrated for starting induction motors, it is not desirable to provide an automatic trip or the toggle 12 in order that the great rush starting current which is from three to four times normal full load, when the motor started, may not open the switch, but in cases where it is desirable to trip both sides, the bar 17 may bemade full length and cooperate with a trip coil the same as she n in the of bar 17. \Vhen the bar 11'' is automatically tripped, it will be unclcrstoolil that the bar is raised turning upon its pi ot-ed end at the front part of the switch, and this action results in the'inclined wall 19 forcing the pin 16 of toggle 12 toward the front of the switch thereby permitting 7 'ing "18 underside z the contacts on? ti..- ,ani against iii occurs so to 8 when t operator the roller 2-4. if an o trip the he" ii, the toy will he collapsed in, la united to fly open ..K.+! n, contin to no the rain a alas? the roller 2?. in again closing the switch. the c ill bc'niovcd to mid-position and the bar 1? moved toward the front of the switch. so that the recess 20 will again engage pin 16, after which the cam may he turned so as to again close the switch. it will also he understood that in g the form oi the switch illustrated either of the toggles l2, l2 he collapsed by inan-v the corresponding bar 1'? or 1'2, since ear. of hers has a recess :26 with sloping wall 19,

It will be in'iderstood that my invention may be embodied in various modifications without departing from the scope of the invention. 7

Having thus described my invention, What- I declare as new and desire to secureby Letters Patent of the United States 1. An electric switch. comprising a plurality of movable contacts, an operating toggle for each, a. bar in operative relation 100 to each to gle respectively for cramping the tog means for moving one of said liars to latch it and release the corresponding tog?" for latching one of said bars to (i toggles, and a rotary 1 5 can; he. -5 provided with a single op r ,1; li'iCzliiFl, d cam engaging each of r i ively for successively (.b'flfllg; contacts by movement oi the different directions. A mliie throw switch, comprising a plurality of toggles and movable contacts operated therebv, a. pivoted cam, operating elements tor toggles, the cam being nioilnt l in operative relation to each of said element for moving them successively for moving ii Quinn-rots in closed position hy dill Y of nmveinent of cain. means finally latching one of said elemen to of said toggles. and 0 means Wilt one of s; kl elements may be v i I l y, 13$ for de iio elements to cam for moving .ively and there toggles for l"\%l}' moving; said mm'able mmtafts Iran; (lll'tflillfllm' Uf mnvement Gf the ram, :2, maxilla for the: cum. :1 manually upmml liatvl; for locking the 021m in an ill- :i liq-mediate position rind means whereby said Plllli'ill'S may he llmifill for releasing the Waikiki 1. .m. elm-(11in witch having a plurality -l mmihlh mimic :1 plurality of togglos i will mntuuh inuunted side by side, and it will in (mumlivu relatiim Lu will, lugglcs i f moving ,nid contacts by u anium in mm'mneni 01' said w ims may bu nmwil to snvvvswiwly ungzigv 3 lab hing n-lnlinnship h; (mu nl' :mii'l lugfgh m nnvlhm 42h: to l illililltl, t :1 ingic (aporutin' many lwi' fur m ning Mill vlvmuiiia HR", VQl 'C 'lur running: th s vlusui'ia (if said minim-is sur- '0.' 1:- i .'0l uml vlmtrii-mzigiiutic means for moving; (2 first nwl'itiunml elvmeut nut vii lnt hing l'ililtlflllhllll) to its rnrrw pmi li1ig toggle anal thi-reliy releasing said togghx 9. Pin :iiitomntiv s iii-h vumpriaing :x ph mill) o movable POHHHLH, nprrziting mglus ilm'u'l'wr rvspecti\'ul x a pliir: lily moms in npvruting' l'QliltlUllblllp with mhl tuggh'a rvspvvti rely and one at least in lutchi115: rv lzitimwhiy with its toggle, single nin-l ilmj manure l'uz' tilh' jfi 7' ply Pligiiglllg'i llhl vlhmvnts for suwossively ('lORlHQ: the rwiirh minim-ts by lnwing thv tugg les to i\' i=--i,-Y pwsilinn. and mums iwr i-m ing' vlmmii iii am-hing 1'i+l;it,im1:-'liip m il mg; L l's in :1 (lll'lvtlflll L0 shill it 1 uurn -1p mliiig i -"jiflr from owl-Set liuiltlull for m sins the 0]): ring m its vm'rvbpiiihling inmizlili mnlzil'l.

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